EESPIEATOEY OEGAXS IN AEAXE^. 
93 
correctly surmises the passage of the blood between the 
saccules and denies the presence of blood-vessels. This is 
the most important description np to Leuckart’s time. 
H. Straus-Durckheim (’28) describes the luug-books of 
spiders, and says one may consider the saccules of these 
organs in Arachnids as non-ramified tracheal trunks, repre- 
senting merely a continuation of the external integument 
in-folded into the interior of the spiracles (pp. 315-318). 
J. F. Brandt (’33, p. 89) gives a poor description of the 
lung-books of Epeira diadema (as gills), apparently 
without knowledge of the work of the two previous authors. 
A. Duges (’36, p. 181) injected spiders’ lung-books with 
carmine. There is also a note on the lung-books in Duges, 
’38, p. 5G8, teste Duvenoy (’40, p. 465). 
G. L. Duvenoy (’40) describes the lung-books of spiders. 
•1. van der Hoeven (’42) describes the lung-books of 
Phyrnus niedius,^ calling them gills. 
G. Newport (’43) describes the appearance of the lamellae in 
scorpions and the circulation of the blood through the lung- 
books (“ branchim ”) (pp. 295-297). 
Pappenheim (’48) has a note on the lung-books of spiders. 
A. Duges (’49) gives figures of the lung-books of Mygale 
(PI. ii, fig. 8, and PI. iv, fig. 6), Segestria (PI. iv, fig. 5), 
Pholcus (PI. iv, fig. 7), and Scorpio (PI. xviii, fig. 1/). 
R. Leuckart (’49) describes the lung-books of scorpions 
and spiders. He discovered the spines of the ante-chamber 
in spiders and recognised the network on the leaves in 
scorpions as a chitinons thread on the surface of the mem- 
brane. He insists that lung-books are merely modifications 
of tracheje (also ’48, p. 119 note), and his paper is the most 
important that appeared before MacLeod’s. 
E. Blanchard (’49, ’50) proved by injection that the blood 
passes through the septa and thence to the heart. 
A. Menge (’51) describes the lung-books of Argyroneta 
(water spider). He failed to find any I'espiratory movements 
' According to Kraepelin ('95, p. 41) v. d. Hoeveu’s species was in 
reality Charon Grayi, Gerv. 
